Cestodes

Question 1

What are the three regions of the adult tapeworm?

Answer 1

the scolex, germinative/neck region, and strobila (main part of the body which is made of proglottids)

Question 2

What are the major features of the cestoda?

Answer 2

Platyhelminths, adults are all endoparasites, no gut, hexacanth larva

Question 3

what is the name of the structure that covers the tegument and increases the surface area x20 to aid in absorption?

Answer 3

Microtriches

Question 4

What are the three types of scolices?

Answer 4

Acetabulate: penetrative and non-penetrative

Bothriate: has shallow sucking grooves

Bothridiate: has four outgrowths called bothridia

Question 5

What is used for the excretory system?

Answer 5

Flame cells

Question 6

How would one treat a tapeworm?

Answer 6

Praziquantel: it opens calcium channels causing the worm die in a contracted state

Question 7

What is the pseudophyllidean life cycle?

Answer 7

Primitive tapeworm group:

Adult > operculated egg > free-swimming coracidium > (in 1st inter host: coepod) proceroid > (2nd inter host: fish) plerocercoid > (def host) adult.

sometimes has a paratenic inter host, a bigger fish, before becoming an adult.

Question 8

what is the cyclophyllidean life cycle?

Answer 8

Advanced tapeworm group:

adult > thick walled eggs w/ hexacanth larva > (in 1st inter host) cysticercus/cysticercoid/cysts or others, (in2nd inter host) mesocestoides, (in def host) adult

can have an accidental, dead end, host after 1st inter host. It can also go straight from 1st inter host to def host.

Question 9

Explain the reproduction within the proglottids of a tape worm?

Answer 9

proglottids from the germinative region mature male parts first, than they age they become female, ideally they become fertilized and eventually they age and pop off of the main body of the tape worm in poop.

Question 10

To self fertilize or to not self fertilize

Answer 10

pro: yaay babies when in a tight spot
con: no more genetic diversity :<

Question 11

Taenia Solium

Answer 11

Pork Tapeworm, armed, cyclophyllidean

Question 12

Taenia pisiformis

Answer 12

Rabbit tapeworm, uses onchospheres and cysticerci, cyclophyllidean

Question 13

What is cysticerci?

Answer 13

The name given to young tapeworms in the genus taenia. It’s a bladder like sac filled with liquid and baby worms and their scolexes.

Question 14

Enchinococcus…

echinococcus granulosus

Answer 14

Hydatid disease, onchospheres, protoscolexes

Body in distinict segments: scolex/head, germative region/neck, immature segment, mature male segment, and mature female/gravoid segment

cyclophyllidean

Question 15

How do tapeworm regulate water?

Answer 15

Tapeworms are osmoconformers but all cestodes are slightly hypotonic to their surroundings in vivo.

Question 16

What problem do Gravid proglottids fix?

Answer 16

Gravid proglottids are able to crawl around a bit. This allows them to distance themselves from the fecal matter they came from. Animals rarely graze near their own feces so this helps with the spreading of the parasite. Some cestodes use insects as intermediate hosts.

Question 17

Which family of tapeworms is NOT hermaphroditic?

Answer 17

Nematioarataeniidae

Question 18

What is premunition?

Answer 18

It’s a phenomenon common with larger tapeworms where the presence of one tapeworm prevents the establishment of others.

Question 19

Diphyllobothrium latum

Answer 19

Dr. Stewart’s IDEAL worm, pseudophyllidean